Display screen or a portion thereof with a graphical user interface



The sole FIGURE is a front view of a display screen or a portion thereofwith a graphical user interface showing a new design.

The broken lines form no part of the claimed design. The outer edge ofthe portion of the display screen is understood to be congruent with theouter edge of the graphical user interface.

CLAIM The ornamental design for a display screen or a portion thereofwith a graphical user interface, as shown and described.